I am working on plotting range-velocity heatmap of the receiving FMCW signal. I actually have already plotted. However, I do not really understand the mapping relationship between Doppler FFT bin and velocity. I learned to map from 1d FFT bin to range with the following codes as the x-axis.
x = (0:ADCsample-1) - ADCsample/2; x = x*Fs/ADCsample; % freq to dist; x = x*3e8/2/slope;
Some notes, I plot the 2D FFT with nFFT = No of chirp in one frame =64.